


# list = [1,2,3,4,5,6,7,8,9,10]
# for i in range(1,21):
#     print(list[i])

try:
    a1 = 3
    a2 = "aaa"
    a3 = 0
    print(a1 + a3)
    a5 = 6
    print(a4)
    a7 = a1 + a5
    print("a7 =",a7)
    # print(a1 / a3)
except TypeError as e1:
    print("捕捉到{}异常，数字和字符串不能进行运算".format(e1))
except NameError as e2:
    print("捕捉到{}异常，有一个变量未定义或名字写错，请检查".format(e2))
except ZeroDivisionError as e3:
    print("捕捉到{}异常，除数不能为0".format(e3))
finally:
    a1 = 3
    a5 = 6
    a7 = a1 + a5
    print("a7 =", a7)



print("999999")
print("999999")
print("999999")
print("999999")
print("999999")
print("999999")
print("999999")